Guarantor And Non-Guarantor Consolidating Condensed Financial Statements (Consolidating Condensed Statements Of Comprehensive Income) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenues
Vehicle rental	$ 1,582	$ 1,211	$ 4,084	$ 3,163
Other	588	412	1,575	1,106
Net revenues	2,170	1,623	5,659	4,269
Expenses
Operating	1,036	783	2,882	2,166
Vehicle depreciation and lease charges, net	436	304	1,088	840
Selling, general and administrative	244	190	696	511
Vehicle interest, net	77	74	231	205
Non-vehicle related depreciation and amortization	30	22	92	65
Interest expense related to corporate debt, net:
Interest expense	67	48	208	143
Early extinguishment of debt	2		52
Transaction-related costs	11	66	21	102
Restructuring charges	7		26	1
Total expenses	1,910	1,487	5,296	4,033
Income (loss) before income taxes and equity in earnings of subsidiaries	260	136	363	236
Provision for (benefit from) income taxes	(20)	54	27	95
Net income	280	82	336	141
Comprehensive income	308	15	361	130
Parent [Member]
Revenues
Other			1
Net revenues			1
Expenses
Operating				2
Selling, general and administrative	5	3	16	8
Interest expense related to corporate debt, net:
Interest expense	2	3	7	7
Intercompany interest expense (income)	(3)		(15)	(8)
Early extinguishment of debt			39
Transaction-related costs	(3)	66		102
Total expenses	1	72	47	111
Income (loss) before income taxes and equity in earnings of subsidiaries	(1)	(72)	(46)	(111)
Provision for (benefit from) income taxes		(27)	(4)	(39)
Equity in earnings (loss) of subsidiaries	281	127	378	213
Net income	280	82	336	141
Comprehensive income	308	15	361	130
Subsidiary Issuers [Member]
Expenses
Operating		1	3	5
Vehicle interest, net				(1)
Non-vehicle related depreciation and amortization			1
Interest expense related to corporate debt, net:
Interest expense	62	46	192	138
Intercompany interest expense (income)	(75)	(46)	(231)	(138)
Early extinguishment of debt	2		13
Total expenses	(11)	1	(22)	4
Income (loss) before income taxes and equity in earnings of subsidiaries	11	(1)	22	(4)
Provision for (benefit from) income taxes	(124)		(118)	(1)
Equity in earnings (loss) of subsidiaries	146	128	238	216
Net income	281	127	378	213
Comprehensive income	307	60	403	200
Guarantor Subsidiaries [Member]
Revenues
Vehicle rental	1,007	995	2,684	2,623
Other	294	282	806	772
Net revenues	1,301	1,277	3,490	3,395
Expenses
Operating	612	615	1,739	1,709
Vehicle depreciation and lease charges, net	267	246	650	686
Selling, general and administrative	153	159	433	427
Vehicle interest, net	60	59	185	166
Non-vehicle related depreciation and amortization	18	20	56	59
Interest expense related to corporate debt, net:
Intercompany interest expense (income)	64	46	205	146
Transaction-related costs			1
Restructuring charges			1	1
Total expenses	1,174	1,145	3,270	3,194
Income (loss) before income taxes and equity in earnings of subsidiaries	127	132	220	201
Provision for (benefit from) income taxes	61	58	96	90
Equity in earnings (loss) of subsidiaries	80	54	114	105
Net income	146	128	238	216
Comprehensive income	172	61	262	203
Non-Guarantor Subsidiaries [Member]
Revenues
Vehicle rental	575	216	1,400	540
Other	616	512	1,593	1,399
Net revenues	1,191	728	2,993	1,939
Expenses
Operating	424	167	1,140	450
Vehicle depreciation and lease charges, net	312	318	736	865
Selling, general and administrative	86	28	247	76
Vehicle interest, net	77	53	232	148
Non-vehicle related depreciation and amortization	12	2	35	6
Interest expense related to corporate debt, net:
Interest expense	3	(1)	9	(2)
Intercompany interest expense (income)	14		41
Transaction-related costs	14		25
Restructuring charges	7		20
Total expenses	949	567	2,485	1,543
Income (loss) before income taxes and equity in earnings of subsidiaries	242	161	508	396
Provision for (benefit from) income taxes	43	23	53	45
Net income	199	138	455	351
Comprehensive income	227	93	483	359
Eliminations [Member]
Revenues
Other	(322)	(382)	(825)	(1,065)
Net revenues	(322)	(382)	(825)	(1,065)
Expenses
Vehicle depreciation and lease charges, net	(143)	(260)	(298)	(711)
Vehicle interest, net	(60)	(38)	(186)	(108)
Interest expense related to corporate debt, net:
Total expenses	(203)	(298)	(484)	(819)
Income (loss) before income taxes and equity in earnings of subsidiaries	(119)	(84)	(341)	(246)
Equity in earnings (loss) of subsidiaries	(507)	(309)	(730)	(534)
Net income	(626)	(393)	(1,071)	(780)
Comprehensive income	$ (704)	$ (214)	$ (1,148)	$ (762)